Sheet metal roofing



N. B. RANDOLPH SHEET METAL ROOFING May 7, 1940.

I Filed June 19, 1939 Patented May 7, 1940 J UNITED STATE SHEET YMEQTAL' ROOFING Nathaniel B. Randolph, Ladue, Mo, assignor to Granite City Steel Company, Inc., Granite City, 111., a corporation of Delaware Application June 19, 1939, Serial No. 279,870 4 Claims (onus-1s) i i This invention relates to sheet metal roofing and more particularly tolap-joints for corrugated sheet metal roofing. It has for its principal objects to provide a waterproof lap-joint 5.1 wherein the lapped margin of a sheet is specially designed to support the lapping margin of an adjacent sheet, to provide gutters for carrying away any Water that enters the joint and to provide air spaces to prevent capillary attraction 10 of the water, and wherein said lapping margin comprises a single corrugation of the same size and shape as the corrugations of a standard corrugated roofing sheet. The invention consists in the sheet, the joint formed by the lapped margins 15 of a plurality of said sheets or by said sheet and the lapping corrugation of a standard corrugated sheet.

In the accompanying drawing which forms a part of this specification and wherein like symgo bols refer to like parts wherever they occur,

Fig. l is a perspective view, showing my improved lap-joint construction,

Fig. 2 is an enlarged fragmentary cross section showing the positions of adjacent sheets before 25 being nailed to the supporting structure; and

Fig. 3 is a view similar to Fig. 2, showing the position of the parts after nailing.

The metal roofing sheets A shown in the accompanying drawing are of standard dimension 30 and the side margin of each sheet overlaps the side margin of an adjacent sheet to form a lapjoint B. Adjacent sheets are secured together and to a suitable support 0, preferably by roofing nails D that are driven through the lap-joints B 35 into the support C. k

The lapped margin of each sheet comprises a relatively low upwardly and outwardly inclined longitudinal edge flange I, a relatively low longitudinal ridge 2 spaced inwardly from said 40 edge flange and a relatively high longitudinal ridge 3 disposed centrally between and cooperating with said relatively low ridge and edge flange to form relatively shallow longitudinal gutters 4 on opposite sides of said relatively high 5 ridge. The remaining portion of each sheet has a continuous series of longitudinal corrugations 5 formed therein preferably of the same size and shape as the corrugations of a standard corrugated roofing sheet.

50 The outermost one of the continuous series of corrugations 5 of each sheet constitutes the entire lapping margin thereof, said corrugation seating on the crest of the relatively high central ridge 3 of the lapped margin of an adjacent 55 sheet, spanning the gutters 4 on opposite sides of said ridge and seating against the edge of the relatively low edge flange I of said lapped margin and against theremote side of the relatively low ridge 2 thereof. The nails D extend downwardly through the crest of the lapping corrugation 5 and 6; the lapped relatively high ridge 3 into the support C, the downward pressure of the nail heads spreading corrugation and rib laterally so that a tight engagement is maintained between said corrugation and ribs 2 and 3 and the edge 10 flange I.

By the arrangement described, a substantial watertight engagement is provided between the overlapped side marginal portions of the sheets along the middle and both sides of the lap-joint, the two gutters are adapted to carry off any water that is driven into the joint and the air spaces above the gutters break the line of contact between said overlapped portions and thus prevent flow of water through the joint by capillary action. The nail holes are located high above the water line of the gutters; and all sharp curves, which tend to break the zinc coating of a galvanized sheet and cause it to rust out, are eliminated. The making of the overlapping margin of the sheet inthe form of a corrugation of the same size and shape as the corrugations of standard corrugated roofing sheets permits damaged or worn standard sheets of existing structures to be replaced with the present sheet without replacing or disturbing the remaining sheets of said structures.

What I claim is:

l. A sheet metal construction composed of metal sheets whose entire width except one side marginal portion is formed into a continuous series oflongitudinal corrugations of uniform size and shape, said marginal portion comprising a relatively low upwardly and outwardly inclined longitudinal edge flange, a relatively low longi tudinal ridge spaced inwardly from said edge flange a distance less than the width of a corrugation and a relativelyhigh longitudinal rib of a depth substantially the same as the depth of said corrugation disposed between and cooperating with said relatively low ridge and edge flange to form relatively shallow longitudinal gutters on opposite sides of said relatively high ridge, the outermost corrugation of each sheet overlapping and contacting with the crest of said relatively high ridge, the edge flange and the relatively low ridge of said lapped marginal portion.

2. A sheet metal roofing construction composed of metal sheets lapped along their side margins, each sheet comprising a continuous series of longitudinal corrugations of the same size and shape except along its lapped margin, the lapped margin of said sheet comprising a relatively low upwardly and outwardly inclined longitudinal edge flange, a relatively low longitudinal ridge spaced inwardly from said edge flange and a relatively high longitudinal rib of substantially the same depth as said corrugations disposed between and cooperating with said relatively low ridge and edge flange to form relatively shallow longitudinal gutters on opposite sides of said relatively high ridge, the outermost corrugation constituting the entire overlapping portion of a sheet and said outermost corrugation bearing on the crest of the relatively high-ridge of the overlapped margin on the upper edge of relatively'lowinclined edge flange and the relatively low ridge of said overlapping margin.

3. A metal roofing sheet or the like whose entire width except one side marginal portion is formed into a continuous series of longitudinal corrugations of uniform size and shape, said marginal portion comprising a relatively low upwardly and outwardly inclined longitudinal edge flange, a relatively low longitudinal ridge spaced inwardly from said edge flange and a relatively high longitudinal rib of a depth substantially the same as the depth of said corrugation disposed between and cooperating with said relatively low ridge and edge flange to form relatively shallow longitudinal gutters on opposite sides of said rela- 1 tively high ridge, the edge of said edge flange, the crest of said high rib and part of the low rib towards the body oi the sheet lying inside a curve corresponding to the cross section of a corrugation of said sheet.

4. A metal roofing sheet or the like comprising a continuous series of longitudinal corrugations of the same size and shape except along one side margin which is formed with a relatively low upwardly and outwardly inclined longitudinal edge flange, a relatively low longitudinal ridge spaced inwardly from said edge flange a distance less than the width of said corrugations and a relatively high longitudinal rib of a depth substantially the same as the depth of said corrugations disposed between and cooperating. with said relatively low ridge and edge flange to form rela-;

tively shallow longitudinal gutters on oppos' e sides of said relatively high ridge. s j NATHANIEL B. RANDOLPH 

